(1) Technical Field
This invention relates to door systems used in the deployment of inflatable restraint safety air bags such as during an automotive collision.
(2) Description of The Prior Art
The deployment of inflatable restraint safety devices into the passenger compartment of a vehicle has presented many engineering challenges. Many of these challenges have been met and problems solved in providing an efficient and safe way to deploy the restraint. One problem that still exists is the occurrence of flying particles and debris which may result during the deployment of the inflatable restraint. The function of the inflatable restraint door assembly is to create a opening in a support structure, commonly an instrument panel, for deployment of the inflatable restraint air bag system during collision situations. The door is displaced out of the instrument panel by the force of the air bag expanding. The opening left behind in the instrument panel allows the air bag to expand into the occupant area. A major concern with inflatable restraint door designs is the occurrence of flying debris during the air bag deployment. Any amount of debris deposited in the occupant area after the bag deployment is considered undesirable and constitutes a failure of the design being evaluated.
An early example of an inflatable safety device can be found in U.S. Pat. No. 3,514,124 issued to Richardson on Mar. 26, 1970. The Richardson '124 patent discloses an inflatable vehicle safety device and an associated exterior panel 22 which is releaseably connected to a nonmoveable member by strips of molding tape 26, 27. When the inflatable restraint is deployed, the panel 22 moves toward the front side of the back seat of the vehicle and the molding tapes 26, 27 are torn or sheared to release the panel 22 during the process. This can cause particles of the tape and other matter to become projectiles within the passenger compartment of the vehicle.
U.S. Pat. No. 3,708,179 issued to Hulten on Jan. 2, 1973 discloses a door assembly for an opening through which an inflatable safety device is deployed. A frame 30 pivotally supports a pair of door elements 38. As is often the case, the inflatable restraint is stored in a compartment on a dashboard or crash pad 12 or some other highly visible place. Typically and as disclosed in the Hulten '179 patent, these visible areas structurally include a base member 14 which supports a cushioning layer 16 which is usually made of urethane foam. A plastisol skin 18, such as vinyl, is then bonded to the urethane foam. Similarly, the front surface 40 of each door element of the Hulten '179 disclosure is covered with the plastisol skin in order to improve the esthetics of the door assembly.
Unfortunately and as often is the case, with time, the plastisol skin has been known to crack or to be susceptible to tearing especially when subjected to cold temperatures.
The subject invention overcomes these deficiencies in the prior art in a safe, superior, and cost effective inflatable restraint door assembly.